Jessica Biel and husband Justin Timberlake have two sons, Silas and Phineas

Jessica Biel's oldest son is unfazed by having famous parents.

The actress, 39, appeared on The Tonight Show Starring Jimmy Fallon on Friday and revealed that while her 6-year-old son Silas recognizes dad Justin Timberlake's music and acting, she can't get him to watch her own children's show, Pete the Cat. 

"Do they kind of freak out because their dad is in Trolls, their mom is in Pete the Cat, they hear these voices and they go 'wait what's going on?' Do they understand what you guys do?" host Jimmy Fallon asked, referencing Silas and the couple's younger son, Phineas

"Silas does definitely with Justin because of Branch," Biel said, noting Timberlake's character in the Trolls movie series. "And also his music — whenever he hears daddy's song he'll go 'Oh yeah, that's dad. No big deal, whatever.' "  

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Jessica Biel and Justin Timberlake
Jessica Biel and Justin Timberlake with son Silas
| Credit: Justin Timberlake/Instagram
Justin Timberlake and Jessica Biel pose for portrait at the Premiere of USA Network's "The Sinner" Season 3 on February 03, 2020 in West Hollywood, California
Justin Timberlake and Jessica Biel
| Credit: Rodin Eckenroth/Getty

She continued, "But the funny thing about Pete the Cat is I tried to get him to watch the show, he will not watch. And yet he says 'hey mom, hey mom, do one of those voices from the show' and I'm like 'But you've never seen the show you don't even know.'" 

"He's just like 'just do it mom,' so I'll do one of the voices and he'll be like, 'cool mom, cool,'" Biel recalled, laughing. 

Jessica Biel, Tonight Show with Jimmy Fallon
Credit: NBC

Earlier in the interview, Fallon, 46, asked whether the actress thinks the two boys are "besties."

"I think they are, I really do and I really was worried you just never know what's going to happen and how your older one is going to feel about the little one," Biel said. "Just think each other are so funny, and it's so amazing to watch." 

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Timberlake, 40, first confirmed he and Biel welcomed a second child during a January episode of The Ellen DeGeneres Show.

"He's awesome and so cute," Timberlake said of the couple's new addition. "Nobody's sleeping, but we're thrilled. We're thrilled and couldn't be happier. Very grateful."